1. Field of the Invention
The present invention relates to a device in a suction tube for surgical or dental use to be connected with a suction conduit, for separating from the suction flow particulate material entrained therein, the suction tube being opened at both ends and has a sieve element located therein.
At surgical operations in bone tissue, for example such operations as are performed in the mouth cavity for different purposes such as fixation of tooth protheses of different types, bone is worked for fastening titanium screws or the like, which are used as anchoring elements. It is desired to take care of tissue fragments which at the working are detached for example as bone chips because these can be used for filling cavities existing in the bone tissue. At the operation a suction device is used in order to remove blood, saliva, and other liquid collected at the operation site. Then, the tissue fragments are sucked away and can get lost if they are not separated from the collected liquid flow. When working in the mouth cavity it is also important to collect metal fragments, for example gold chips, at grinding of bridges and crowns, or amalgam which has been drilled from teeth or is spilt when filling a tooth cavity. The sieve element also prevents screws and other small components used in implant constructions, or gold and porcelain inserts or crowns to be accidentally sucked into the suction system.
2. Description of the Prior Art
U.S. Pat. No. 5,688,121 discloses a flexible suction tube which at the outlet end has a disc-shaped filter element attached in the suction tube for separating amalgam from the suction flow. The filter element is attached in a ring which in turn is attached in the suction tube, so that the plane of the filter element is located across the flow, i.e. perpendicularly to the longitudinal axis of the suction tube.
A similar filter device is disclosed in U.S. Pat. No. 5,078,603. The filter is mounted in a suction tube for one way use so that it is scrapped after having been used on a patient, the disgusting handling in connection with cleaning of the filter thus being avoided.
However, these solutions as far as they are used in surgical and dental applications both cause clogging of the filter element because the material that has been separated will collect on the filter and will block the passage through the suction tube via the filter.